Benzothiazole azo compounds containing a reactive methylene coupling component



United States Patent BENZOTHIAZQLE AZO COMPOUNDS CONTAIN- ING A REACTIVE METHYLENE COUPLING COMPONENT James M. Straley and John G. Fisher, Kingsport, Tenn., assignors to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey No Drawing. Application March 1, 1955 Serial No. 491,546

18 Claims. (Cl. 260-146) This invention relates to new azo compounds and their application to the art of dyeing or coloring. More particularly, it relates to certain metallized and non-metallized benzothiazole azo compounds containing a reactive methylene coupling component and their application to the dyeing of various textile materials. Insofar as dyeing or coloring is concerned the invention is particularly directed to the dyeing or coloring of cellulose acetate textile materials with the metallized azo compounds of the invention.

The non-metallized monoazo compounds of our invention have the formulas:

wherein Ar represents an ortho-arylene radical of the benzene series, X represents the radical of a monocyclic benzene compound, the radical of a naphthalene compound, a phenylamino radical or the radical of a styryl compound, Q represents a methyl group, a trifluoromethyl group or the radical of a monocyclic benzene compound, R represent the radical of a monocyclic benzene compound or the radical of a naphthalene compound, Q represents a methoxy group or an ethoxygroup and Y represents the radical of a monocyclic benzene compound or a trifluoromethyl group. The metallized azo compounds of our invention comprise the monoazo compounds having the Formulas l, 2 or 3 in complex combination with chromium, cobalt, copper, iron, manganese, nickel and vanadium. The manner of preparing the non-metallized and metallized azo compounds of our invention is fully described hereinafter.

As is Well known, one of the disadvantages dyed cellulose acetate textile fabrics sufier in comparison with some of the dyed competing textile fabrics, such as cotton, wool and viscose, for example, is lack of fastness to washing. Many schemes have been proposed to remedy this situation but all suffer from some significant fault. By means of our invention dyed cellulose acetate textile materials having good to excellent fastness to washing, light and gas are obtainable. These results may be obtained by dyeing the cellulose acetate textile material with the non-metallized dye compounds of the invention and then treating the dyed cellulose acetate textile material with suitable metal salts which cause the original dye to form metallic complexes which are resistant, for example, to the action of washing, light and gas. Thus, by means of the present invention, the disadvantage noted above with respect to the wash fastness of dyed cellulose acetate textile materials is either entirely or largely overcome.

While reference has been made to the dyeing of cellulose acetate textile materials, it is to be understood that the invention is generally applicable to the dyeing of textile materials made of or containing a cellulose alkyl carboxylic acid ester having two to four carbon atoms in the acid groups thereof. By cellulose alkyl carboxylic acid esters having two to four carbon atoms in the acid groups thereof, we mean to include, for example, both hydrolyzed and unhydrolyzed cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate-propionate and cellulose acetate-butyrate. Cellulose acetate has been particularly referred to because it is the most widely used cellulose alkyl carboxylic acid ester.

The non-metallized monoazo compounds of our invention are prepared by diazotizing a Z-aminobenzothiazole compound having the formula:

to s

wherein Ar represents an ortho-arylene radical of the benzene series and coupling the diazonium compound obtained with a reactive methylene compound selected from those having the formulas:

wherein Q, Q, R, X and Y have the meaning previously assigned to them.

These compounds, in addition to being dyes for various materials identified herein, possess the important property. of being metallizable. The metallized dyes formed therefrom have the valuable properties described herein.

The metallized monoazo compounds of our invention are prepared by treating the non-metallized azo compounds having the Formulas l, 2 or 3 with salts of nickel, cobalt, copper, chromium, manganese, iron or vanadium. The non-metallized monoazo compounds can be metallized either on or off the fiber. Metallization can be carried out, for example, by treating the non-metallized dye with a solution or dispersion of the metallizing agent. Although the metal complex is often formed at room temperature, we prefer to accelerate the process by heating, usually with steam, for a short time. The preparation of the metallized monoazo compound of our invention is fully described hereinafter.

sulfate, nickel acetate, nickel cyanide, nickel formate, nickel thiocyanate [Ni(SCN) cobaltous bromide, cobaltic chloride, cobaltous chloride, cobaltous acetate, cobaltous cyanide, cobalt thiocyanate [Co(SCN) cupric chloride, cupric bromide, cupric acetate, cupric lactate, chromium trichloride, chromium tribromide, chrornic sulfate, chromic acetate, chromium thiocyanate manganese chloride, manganous sulfate, manganese acetate, manganese thiocyanate [Mn(SCN) ferric chloride, ferric fluoride, ferrous acetate, ferrous thiocyanate [Fe(SCN) ferric thiocyanate [Fe(SCN) and vanadium tribromide, are illustrative of the metallizing agents that can be employed. I

When the metal complex is formed on a cellulose alkyl carboxylic acid ester, such as cellulose acetate, fiber the use of a metal thiocyanate appears to be advantageous and is preferred. Nickel thiocyanate appears to be especially useful and particular claim is laid to its use. Next to nickel thiocyanate the use of cobalt thiocyanate is preferred.

2 amino 6 methylsulfonylbenzothiazole, 2 amino- 6-ethylsulfonylbenzothiazole, 2-amino-6-npropylsulfonylbenzothiazole, 2 amino 6 n butylsulfonylbenzothiazole, 2-aminobenzothiazole-6-N methylsulfonamide, 2- aminobenzothiazole 6 N ethylsulfonamide, 2 aminobenzothiazole 6 N n propylsulfonamide, 2 aminobenzothiazole 6 N n butylsulfonamide, 2 amino- 6 methoxybenzothiazole, 2 amino 6 ethoxybenzothiazole, 2 amino 6 n propoxybenzothiazole, 2- amino 6 n butoxybenzothiazole, 2 amino 6 methylbenzothiazole, 2 amino 6 ethylbenzothiazole, 2-

amino 6 n propylbenzothiazole, 2 amino 6 nbutylbenzothiazole, 2-arnino-6-B-hydroxyethylbenzothiazole, 2 amino 6 "y hydroxypropylbenzothiazole, 2- amino 6 6 hydroxybutyl'benzothiazole, 2 amino- 6- acetylaminobenzothiazole, 2 amino 6 n propionylaminobenzothiazole, 2 amino 6 n butyrylaminobenzothiazole, 2 amino 6 thiomethylbenzothiazole, 2 amino 6 thiocyanobenzothiazole, 2 amino 6 cyanobenzothiazole, 2 amino 6 trifiuoromethylbenzothiazole, 2 amino 6 chlorobenzothiazole, 2 amino- 6 nitrobenzothiazole, 2 amino 4,7 dimethoxybenzothiaozle, 2 amino 5,6 dimethoxybenzothiazole, 2- amino 4,7 diethoxybenzothiazole, and 2 amino 4,6- dimethylbenzothiazole are representative of the 2-aminobenzothiazole compounds used in the preparation of the azo compounds of our invention.

Acetoacetanilide, acetoacet 2 methoxyanilide, acetoacet-4-methoxyanilide, acetoacet-2-methylanilide, acetoacet-2,4-di-methylanilide, acetoacet-2chloroanilide, acetoacet 4 chloroanilide, acetoacet 2,4 dichloroanilide, acetoacet-4-nitroanilide, acetoacet-3methylolanilide, acetoa-cet 4 B hydroxyethylanilide, trifluoroacetoacetanilide, trifiuoroacetoacet 2 methoxyanilide, trifiuoroacetoacet 2 methylanilide, trifiuoroacetoacet 2 chloroanilide, trifiuoroacetoacet 4 chloroanilide, trifluoroacetoacet 4 nitroanilide, cyanoacet 4 nitroanilide, cyanoacet 2 methylanilide, cyanoacet 4 methylanilide, cyanoacet 2 chloroanilide, cyanoacet 4 chloroanilide, benzoylacetonitrile, m-nitrobenzoylacetonitrile, p nitrobenzoylacetonitrile, o chlorobenzoylacetonitrile, p chlorobenzoylacetonitrile, o methylbenzoylacetonitrile, o methoxybenzoyla-cetonitrile, benzoylacet 4- benzamido-2,S-dimethoxyanilide, methyl trifiuoroacetoacetate, methyl p-nitrobenzoyl acetate, ethyl-p-nitrobenzoyl acetate, methyl benzoyl acetate, ethyl benzoylacetate, cinnamoylacetonitrile, pnitrocinnamoylacetonitrile, o-chlorocinnamoylacetonitrile, o-methylcinnamoylacetonitrile, Z-cyanoacetonaphthalene and 2-acetoacetnaphthalide, are illustrative of the reactive methylene coupling compounds used in the preparation of the azo compounds of our invention.

The non-metallized monoazo dye compounds of our invention have varying utility for the dyeing of cellulose alkyl carboxylic acid esters having two to four carbon atoms in the acid groups thereof, nylon, acrylonitrile polymers, such as polyacrylonitrile and acrylonitrile graft polymers, and polyesters, such as polyethylene terephthalate. After application to these materials, usually in the form of textile materials, the dye may be metallized thereon, if desired. The metallized azo compounds of our invention can be applied by ordinary dyeing or printing techniques to nitrogenous textile materials such as wool, silk, nylon and acrylonitrile polymers, for example. Coloration can also be effected by incorporating the nonmetallized or metallized azo compounds into the spinning dope, spinning the fiber as usual and converting the nonmetallized azo compounds to their metallized form if desired. Also the metallizing agent can be incorporated in the spinning dope, the fiber spun as usual and then dyed with the non-metallized monoazo compounds to form the metal complex on the fiber. The new metallized dyes of our invention are preferably formed by heating the nonmetallized azo dye with the metallizing agent in organic solvents, such as, for example, cellulose acetate, cellulose acetate-propionate, acrylonitrile polymers, polyamides methyl Cellosolve and formamide.

Both the non-metallized and metallized monoazo compounds of our invention are dyes for fibers prepared from graft polymers obtained by graft polymerizing acrylonitrile alone or together with one or more other monoethylenic monomers with a preformed polymer. The preformed polymer can be a homopolymer (a polymer prepared by polymerization of a single monomer) or it can be an interpolymer such as a copolymer (a polymer prepared by the simultaneous polymerization in a single reaction mixture of two monomers) or a terpolymer (a polymer prepared by the simultaneous polymerization in a single reaction mixture of three monomers), or the like, and the graft polymers for which the dyes are particularly useful are those containing at least 5% by weight of combined acrylonitrile grafted to the preformed polymer molecule. 1

The graft polymers which can be dyed using the nonmetallized and metallized dyes are thus polymers having directed placement of the polymerized monomeric units in the graft polymer molecule as distinguished from the random distribution obtained in interpolymers which are prepared by simultaneous polymerization of all of the monomeric materials in the polymer. The preformed polymer can be either a homopolymer of any of the wellknown polymerizable monomers containing a single CH=C group and desirably a CH =C group, or

. an interpolymer of two or more of such monomers; and

the grafting can be effected with the preformed homopolymer or interpolymer in the polymerization mixture in which it was formed (i. e. a live polymer) or with the preformed polymer isolated from the polymerization mixture in which it was formed (i. e. a dead polymer).

The preformed polymer desirably is a homopolymer of a vinyl pyridine, an acrylamide, a maleamide, a fumaramide, an acrylate, a methacrylamide, a methacrylate, an itaconamide, a citraconamide, a fumaramate, an itconamate, a citraconamate, a malemate, or avinyl ester; or an interpolymer of two or more of such monomers with each other or of at least one of such monomers with one or more different monoethylenic monomers characterized by a CH=C group such as styrene, acrylonitrile, substituted styrenes, vinyl or vinylidene chlorides, vinyl ethers, dialkyl maleates, alkenyl ketones, dialkyl fumarates, acrylic acid, methacrylic acid, substituted acrylonitriles, fumaronitrile, ethylene and the like.

The graft polymerization is effected by polymerizing acrylonitrile or a mixture of acrylonitrile with any other monoethylenic monomer, including any of the monomers enumerated hereinabove, with the preformed live or dead homopolymer or interpolymer whereby the aclylonitrile 5 alone or together with :another grafting monomer is combined with the preformed polymer molecule to give a graft polymer containing from 5 to 95% by weight of combined acrylonitrile.

The new azo compounds of our invention are of particular utility for dyeing fibers prepared from a graft polymer obtained by graft polymerizing acrylonitrile and EXAMPLE 1 130 parts of concentrated sulfuric acid (94%) were added at room temperature to a slurry of 11.4 parts of 2-amino-6-methylsulfonylbenzothiazole in 120 parts of water. The temperature of the reaction mixture rose to about 90 C. and the 2-amino-6-methylsulfonylbenzothiazole dissolved. After cooling the reaction mixture to 10 C., at which temperature a precipitate formed, a solution of 4.2 parts of sodium nitrite in 47 parts of sulfuric acid was carefully added to the reaction mixture, 'with stirring, while keeping the temperature of the reaction mixture below -5 C. After stirring for 2 hours at 5 C., the diazonium solution resulting was added to a solution of 10.4 parts of acetoacet-2-methoxyanilide in 150 parts of propionic-acetic (1:5) acids below 5 C. and the resulting reaction mixture was held at this temperature for 1 hour with good stirring. The reaction mixture was then made neutral to Congo red paper by the addition of ammonium acetate following which it was drowned in 2000 parts of cold water. The yellow solid which precipitated was recovered by filtration, washed with water until neutral and then dried at 60 C. 17.8 parts of the dye compound having the formula:

I OCHa were obtained. This dye compound colors cellulose acetate pale yellow shades.

EXAMPLE 2 50 parts of propionic-acetic (1:5 acids were added at 5 C. to a solution of 3.8 parts of sodium nitrite in 47 parts of concentrated sulfuric acid. A solution of 9.1 parts of 2-amino6-methoxylbenzothiazole in 50 parts of propionic-acetic (1:5 acids was added at 5 C. to the sodium nitrite solution and the resulting mixture was stirred for 2 hours at C. to C. The diazonium solution thus obtained was added at 5 C. to a solution of 8.9 parts of acetoacetanilide in 150 parts of propionicacetic (1:5 acids. The reaction mixture thus obtained was stirred for 2 to 3 hours at 0-5 C. following which the reaction mixture was made neutral to Congo red paper with ammonium acetate to neutralize the mineral acid present (sodium acetate can be used in place of ammonium acetate). The reaction mixture was then drowned in 2000 parts of cold water and the dye product which precipitated was recovered by filtration, washed well with cold water and dried at 60 C. 17 parts of a dye compound which colors cellulose acetate pale yellow tints were obtained.

6 EXAMPLE 3 9.75 grams of Z-amino-6-nitrobenzothiazole were dissolved in 250 grams of 50% aqueous sulfuric acid and the resulting solution was cooled to 5 C. A solution of 4.2 grams of sodium nitrite in 25 cc. of concentrated sulfuric acid was added with good stirring while holding the temperature between 0 C. and 5 C. The diazonium solution resulting was stirred for 2 hours at a temperature between 0 C. and 5 C. and then added at 0 C. to a solution of 7.3 grams of benzoylacetonitrile in 150 cc. of propionic-acetic (1:5 acids. The reaction mixture was allowed to stand 1.5 hours longer at about 0 C. and then drowned in 2000 cc. of cold water. The dye product which precipitated was recovered by filtration, washed well with cold water and dried. 16 grams of dye compound were obtained as a yellow solid which dyes cellusose acetate deep yellow shades and which colors the acrylonitrile graft polymer specifically described hereinafter shades having good light fastness and good wash fastness were obtained.

EXAMPLE 4 By the use of 7.3 parts of benzoylacetonitrile in place of acetoacetanilide in Example 2 15.1 parts of a dye product which colors cellulose acetate yellow shades and which colors the acrylonitrile graft polymer specifically described hereinafter light-fast shades were obtained.

EXAMPLE 5 By the use of 9.6 parts of acetoacet-2-methylanilide in place of acetoacet-Z-methoxyanilide in Example 1, 17.8 parts of a dye compound which colors cellulose acetate, nylon, wool and the acrylonitrile graft polymer specifically described hereinafter rich lemon-yellow shades were obtained.

EXAMPLE 6 By the use of 10 parts of acetoacet-2,4dimethylanilide in Example 1 in place of acetoacet-Z-methoxyanilide 18.3 parts of a yellow dye compound is obtained which colors cellulose acetate, nylon, wool and the acrylonitrile graft polymer specifically described hereinafter yellow shades.

EXAMPLE 7 5 grams of the dye product of Example 5 were dissolved in cc. of methyl Cellosolve. 2.5 grams of nickelous acetate and 4.5 grams of sodium carbonate were added and the reaction mixture resulting was refluxed with stirring for 8 hours and then poured into 1000 cc. of cold water. The reaction product which precipitated was recovered by filtration, washed well with water and dried. 5.7 grams of a yellow pigment (the nickel complex of the dye product of Example 5) which, when dispersed by grinding in cellulose acetate dope and extruding, produces yellow yarn of excellent light and wash fastness were thus obtained.

EXAMPLE 8 6 grams of the dye produce of Example 3 were heated to 100 C. in 100 grams of formamide and- 18 cc. of a 12% solution of nickel thiocyanate were added while stirring. The reaction mixture was held at a temperature of 90 C.- C. for 1 hour while keeping slightly alkaline by the addition of 28% NH OH after which it was drowned in 1500 cc. of cold water. The reaction product which precipitated was recovered by filtration, washed well with water and dried. 6.3 grams of a pigment (the nickel complex of the dye product of Example 3) which, when milled into cellulose acetate on a hot roll, for example, yields sheets of an attractive red shade highly resistant to the action of light and wet processing were thus obtained.

EXAMPLE 9 By the use of 5.96 grams of the dye product of Example 4 in place of the dye product of Example 3 in Example 8 a pigment which is the nickel complex of the dye product of Example 4 is obtained. This pigment, when incorporated by known means into films, filaments, etc. of cellulose acetate, imparts red shades of good fastness properties thereto.

The nickel complex of the dye product of Example 4 can also be prepared, for example, by using the general procedure described in Example 7.

EXAMPLE 10 By the use of 7.6 grams of the dye product of Example 1 in place of the dye product of Example 3 in Example 8 the nickel complex of the dye product of Example 1 is obtained. This pigment product, when incorporated by known means into films, filaments, etc. of cellulose acetate, imparts yellow shades of good fastness properties thereto.

The nickel complex of the dye product of Example 1 can also be prepared using the general procedure described in Example 7.

EXAMPLE 11 By the use of 6.3 grams of the dye product of Example 2 in place of the dye product of Example 3 in Example 8 the nickel complex of the dye product of Example 2 is obtained. This pigment product, when incorporated by known means into films, filaments, etc. of cellulose acetate, imparts orange shades of good fastness proper ties thereto.

The nickel complex of the dye product of Example 2 can also be prepared using the general procedure described in Example 7.

EXAMPLE 12 EXAMPLE 13 A cellulose acetate delustered tricot fabric dyed with a 3% dyeing of the dye product of Example 1 was padded with a 2% aqueous solution of nickel thiocyanate under conditions such that a 60 to 100% pick-up based on the weight of the fabric was obtained. The cellulose acetate fabric was air dried and then aged in a steam chest at p. s. i. pressure for 20 minutes following which it was scoured at 60 C. with soap and water, rinsed well with warm water and dried. By this treatment the original yellow dyed fabric was dyed a pleasing lemon-yellow shade which is much stronger tinctorially than that of the original dyeing. N-o bleeding was observed when a sample of the dyed fabric was subjected to a standard AATCC wash test at 160 F. with soap and water. Further, while the original yellow dyeing showed a break after 4 hours on the Fade-Ometer, the metallized dyeing showed no fading after 20 hours exposure on the Fade- Ometer.

8 EXAMPLE 14 A cellulose acetate delustered tricot fabric dyed with a 3% dyeing of the dye product of Example 2 was padded with a 2% solution of cobalt thiocyanate under conditions such that a 60 to pick-up based on the weight of the fabric was obtained. The cellulose acetate fabric was air dried and then aged in a steam chest at 5 p. s. i. pressure for 20 minutes following which it was scoured at 60 C. with soap and water, rinsed well with warm water and dried. By this treatment the original yellow dyed fabric was dyed an orange shade having excellent fastness to light and washing.

EXAMPLE 15 A cellulose acetate delustered tricot fabric dyed with a 3% dyeing of the dye product -of Example 1 was padded with a solution of 6 parts of Cuprofix (a minxture of copper sulfate and a low urea-formaldehyde resin) in 200 parts of water and then dried at C. The dyed, padded cellulose acetate fabric was then cured at C. for 5 minutes and then scoured for 5 minutes at 60 C. with a solution of 1 part sodium carbonate, 1 part Calgon (sodium hexa-meta-phosphate) and 1 part Igepal CA (a polymerized ethylene oxide-alkyl phenol condensation product) in 100 parts of water, rinsed with water and dried. The cellulose acetate fabric was dyed a yellowish-brown shade having excellent fastness to light and washing.

EXAMPLE 16 A cellulose acetate yarn containing 1% of CrCl (spun in during manufacture of the yarn) was dyed in the usual manner with the, dye product of Example 2. A 3% dyeing was prepared. The dyed yarn was then steamed at 5 p. s. i. for 30 minutes, scoured with soap as in Example 15 and rinsed with water. The cellulose acetate yarn is dyed a yellow shade having superior fastness to the action of laundering agents.

EXAMPLE 17 In Example 4 the 6-methoxy-2-aminobenzothiazole is replaced by an equal amount of 4-methoxy-2-aminobenzothiazole. After proceeding as before a material is obtained which imparts to the acrylonitrile graft polymer specifically described hereinafter fast shades.

EXAMPLE 18 One gram of the product of Example 17 is dissolved in 30 cc. of acetone. At the boil there is added 1 cc. of 28% ammonium hydroxide, followed by 5 cc. of a 17% aqueous solution of nickel thiocyanate. The mix is stirred and refluxed for two hours and drowned in 250 cc. of cold water. The product is isolated by filtering, washing with cold water, and drying at 60 C. in vacuo. When dispersed by known means in a cellulose acetate solution in acetone and cast or extruded, reddish orange films and fibers of excellent fastness to light and wet-processing are obtained.

The following tabulation further illustrates the monoazo compounds of our invention and sets forth the colors the non-metallized compounds yield on cellulose acetate, an acrylonitrile graft polymer and nylon, as well as the colors obtained on cellulose acetate when the non-metallized compounds are metallized on the fiber. The preparation of the acrylonitrile graft polymer referred to in ,the tabulation is described immediately following the -cinnamoylacetonitrile has the formula v Color o!1 CA Color on'A'crylo- 2-Aminohenzoth1azole Coupling; Component Metallizmg nitrile Graft Compound Agent Polymer and l I Original Final Nylon Original yellow.

0 Do. is'flzo i'efii Efiiiiio -.2,5 (i1 6 Do.

methoxyanilide. do

Do. 0 S N)2 d AcetgaacetQ-methylanilide G Do. O

Benoylacetonitrfle" N (SO O Benoylacetonitrilen O Ethgl p-nitrobenzoyl acetate O Oingamoylacetonitrileo l d Acetoacetanilide. Do. do d For purposes of-clarity methyl trifiuoroacetoacetate has and ethyl p-nitrobenzoyl acetate has the formula the formula CF COCH COOCH trifluoroacetoacetanilide has the formula om-G-o 0 CH2C o 0 02115 Q O OHZO O 0 F3 Preparation of trifluoroacetoacetanilide 70 A solution of 0.4 g. of triethanolamine in 0.6 g. of ethanol was added to 105 cc. of xylene, which was then boiled removing 5 cc. of xylene. There'was then added 41.5 g. of ethyl trifluoroacetoacetate. The solution was brought to reflux and a mix of 18.6 grof aniline in 25 Ce.

OCH=CHCOCH2CN 75 of xylene was added during 2 hours. The alcohol -pro- 11 duced was distilled off as it was formed. Reflux was continued until the temperature reached 130 C. The mix was cooled at C. for 36 hours and the white solid filtered off and washed with hexane. The yield was 20 g. of product melting at 75-76 C. Other substituted trifluoroacetoacctanilides were prepared in a similar manner by starting from the appropriate amine instead of aniline.

Preparation of acrylonitrile graft polymer 3.0 g. of acrylonitrile and 7.0 g. of N-methyl methacrylamide were emulsified in 40 cc. of water containing 0.15 g. of potassium persulfate and 0.01 g. of tertiary dodecyl mercaptan. The emulsion was heated at 60 C. until 94% or more of the monomers had copolymerized. This result is usually accomplished by heating for about 12 hours. The copolymer contained approximately 30% by weight of acrylonitrile and 70% by weight of N-methyl methacrylamide. The mixture was then cooled to room temperature, 50 cc. of water added and the mixture agitated until a homogeneous solution of dope containing by weight of the copolymer resulted.

30.7 g. (3.07 g. of copolymer) of the above prepared solution or dope of the copolymer were placed in a jacketed reactor provided with an agitator and heat exchanger. There were then added 10 g. of acrylonitrile, 114 cc. of water, 0.58 g. of 85% phosphoric acid, 0.1 g. of potassium persulfate, 0.17 g. of potassium metabisulfite, 0.1 g. of tertiary dodecyl mercaptan and 0.56 g. of a 30% solution in water of N-methyl methacrylamide and the mixture heated, with stirring, to 35 C. and then allowed to level off at 37-39 C. After the heat of polymerization had been removed and when the conversion of the acrylonitrile to polymer had reached 96% or more, which is usually accomplished in a period of about 12 hours, the temperature was raised to 90 C. The mother liquor was removed by centrifuging the polymerization mixture, the polymer precipitate being reslurried twice with water and centrifuged to a 70% moisture cake. The cake was dried under vacuum at 80 C. in an agitated dryer. The over-all yield of modified polyacrylonitrile product was over 90%. After hammer-milling, the dry powder, now ready for spinning, was stored in a moisture proof container.

The acrylonitrile graft polymer prepared as above and containing about 18% by weight of N-methyl methacrylamide was soluble in N,N-dimethylformamide. Fibers spun by extruding a solution of the polymer product in N,N-dimethylformamide into a precipitating bath had a softening temperature of about 240 C., an extensibility of about 20-30 percent depending on the drafting and relaxing conditions, and showed excellent aflinity for dyes.

In order that the preparation of the azo compounds of our invention may be entirely clear, the preparation of certain intermediates used in their manufacture is described hereinafter.

Preparation of 2-amino-6-methylsulfonylbenzothiezole A solution of 200 parts of bromine in 300 parts of acetic acid was added over the course of about 1 hour to a mixture of 171 parts of p-aminophenylmethylsulfone and 202 parts of sodium thiocyanate in 1750 parts of acetic acid. The temperature was held below 35 C. during the addition and after complete addition of the bromine-acetic acid mixture, the reaction mixture was stirred for 18 hours. The reaction product was recovered on the filter by filtration, washed with acetic acid and then dispersed in 6000 parts of water. The reaction mixture thus obtained was heated to boiling and then an alkali such as caustic soda or sodium carbonate was added until the pH of the reaction mixture was about 6. The reaction mixture was then cooled, filtered and the reaction product which collected on the filter was washed 2 well with water and dried at C. to parts of 2-amino-6-methylsulfonylbenzothiazole were obtained as light yellow crystals melting at 226 C.228 C.

Preparation of 2-acetylamino-6-thiocyanobenzothiazole To a solution of 18.6 parts of aniline and 30.4 parts of ammonium thiocyanate in 300 parts of acetic acid at 15 C. 14.2 parts of chlorine were bubbled in at 15 C.- 17 C. 30 minutes after addition of the chlorine 15.6 parts of sodium acetate and 30.4 parts of ammonium thiocyanate were added to the reaction mixture. While holding the temperature of the reaction mixture below 35 C., 14.2 parts of chlorine were passed in and the reaction mixture was stirred overnight at room temperature. The solid present in the reaction mixture was recovered by filtration, washed with 50 parts of acetic acid and then suspended in 600 parts of water. The mixture thus obtained was heated to boiling and filtered. 30 parts of sodium acetate were added to the filtrate and the solid which precipitated was collected at 70 C. on a filter, washed with 200 parts of cold water and dried at 100 C. 30 parts of a product melting at 187 C.- 188 C. were thus obtained.

30 parts of acetic anhydride were added at 80 C. to a solution of 52.6 parts of the above product in 81 parts of acetic acid, and the temperature of the reaction mixture was held at 80 C.-90 C. for one hour. The reaction mixture was then poured into 1000 parts of cold water and the product which precipitated was recovered by filtration, washed with 500 parts of water and then dried at 60 C. 62 parts of 2-acetylamino-6-thiocyanobenzothiazole melting at 247 C.-249 C. were thus obtained.

Preparation of 2-amino-6-ethylsulfonylbenzothiazole A solution of 26.4 parts of crystalline sodium sulfide and 24.9 parts of 2-acetylamino-6-thiocyanobenzothiazole in 150 parts of ethyl alcohol were refluxed together for 10 minutes and after cooling the reaction mixture to 20 C., 16.3 parts of ethyl iodide were added at one time and the reaction mixture resulting was refluxed for one hour. The reaction mixture was then poured into 1000 parts of water and the product which precipitated was recovered by filtration, washed well with water and dried at 60 C. 23.6 parts of 2-acetylamino-6-ethylthiobenzothiazole melting at 168 C.169 C. were obtained. If desired, the quality of the product can be checked by hydrolyzing a little of the product with acid to 2-amino-6-ethylthiobenzothiazole melting at 137 C.139 C.

19 parts of 30% aqueous hydrogen peroxide were added to a solution of 15.5 parts of 2-acetylamino-6- ethylthiobenzothiazole in 53 parts of acetic acid while maintaining the temperature of the reaction mixture between 80" C.90 C. The reaction mixture was maintained at this temperature for one hour and then poured into 500 parts of cold water. The solid present in the reaction mixture was recovered by filtration and then suspended in a mixture of 800 parts of water and 100 parts of concentrated hydrochloric acid. The reaction mixture thus obtained was heated to boiling and then filtered. The filtrate was neutralized with sodium acetate, cooled to 25 C. and filtered. The product collected on the filter was washed with cold water and dried at 60 C. 8.5 parts of 2-amino-6-ethylsulfonylbenzothiazole melting at 173 C.-175 C. were thus obtained.

Preparation of 2-amino-6-isopropylsulfonylbenzothiazole Preparation of Z-amino-6-isoburylsulfonylbenzo thiazole I of isobutyl bromide in the foregoing example.

Preparation of 2-amin0-6-triflu0romethylsulfonylbenzothiazole 75 parts of bromine in 120 parts .of acetic acid were added gradually with stirring to a solution of 98 parts of p-aminophenyltrifiuoromethylsulfone and 76 parts of sodium thiocyanate in 700 parts of'acetic acid. The addition of the bromine was begun .at room temperature and the temperature of the reaction mixture was kept below 35 C. during the addition. The temperature ordinarily rises to about 32 C. The reaction mixture resulting was stirred for 24 hours at room temperature following which it was poured into 5000 parts of cold water and the mineral acid therein neutralized by the addition of sodium acetate with good stirring. The product which formed was recovered by filtration, washed well with cold water and dried at 110 C. 33 to 70 parts of 2-amino-6-trifluoromethylsulfonylbenzothiazole melting at 206208 C; were thus obtained.

Preparation of 2-amino6-trifluoromethylbenzothiazole 12.5 parts of bromine in 20 parts of acetic acid were added dropwise, with stirring, to a solution of 12.4 parts of p-aminobenzotrifiuoride and 12.7 parts of sodium thiocyanate in 115 parts of acetic acid while maintaining the temperature of the reaction mixture below 35 C. The reaction mixture resulting was stirred for 12 hours following which the solid present therein was removed by filtration. The filtrate was poured into 1000 parts of water and the mineral acid therein was neutralized by the addition of sodium acetate with good agitation. .The product which formed was recovered by filtration, washed well with cold water and dried under vacuum at 45 C. 7.7l0.2 parts of Z-amino-6-trifluoromethylbenzothiazole melting at 115.5 116.5 C. were thus obtained.

Preparation of 2-amino-6-l3-hydroxyethylbenzothiazole 255.7 grams of bromine in 400 cc. of acetic acid were added gradually over a period of 1 hour with good stirring to a solution of 219.2 grams of p-aminophenylethyl alcohol and 259.2 grams of sodium thiocyanate in 2400 cc. of acetic acid while maintaining the temperature of the reaction mixture below 15 C. The reaction mixture resulting was stirred for 2 hours at 10-12 C. and the product which formed was recovered on the filter by filtration and washed with 300 cc. of acetic acid. The product filter cake thus obtained was dissolved in 1600 cc. of water at about 40 C. and the reaction mixture was made alkaline by the addition of sodium hydroxide. The reaction mixture thus obtained was heated to boiling and then cooled to C. and filtered. The product obtained on the filter was Washed with water until neutral and then dried at 100 C. 206 to 230 grams of 2-amino-6-[3-hydroxyethylbenzothiazole were thus obtained in the form of white crystals melting at 175 -177 C.

Another alkali metal thiocyanate such as potassium thiocyanate, for example, can be used in place of sodium thiocyanate in the foregoing examples. Similarly, an other alkaline agent, such as sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, ammonium acetate or potassium acetate, for example, can

beused to neutralize the mineral acid in place of sodium acetate.

The preparation of p-aminophenyltrifluoromethylsulf-one is described in British Patent 485,592.

The non-metallized monoazo dye compounds of our invention can be applied to cellulose alkyl carboxylic acid esters having 2 to 4 carbon atoms in the acid groups thereof, .nylon, an acrylonitrile polymer, such as polyacrylonitrile and acrylonitrile graft polymers, and polyester, such as polyethylene terephthalate, textile materials and the metallized azo dye compounds of our invention can be applied to nitrogenous textile materials such as, for example, wool, silk, nylon and acrylonitrile polymers, such as polyacrylonitrile and acrylonitrile graft polymers, in the form of an aqueous dispersion and are ordinarily so applied.

To illustrate, the dye compound is finely ground with a dispersing agent such as sodium lignin sulfonate, Turkey red oil, soap, or an oleyl glyceryl sulfate and the resulting mixture is dispersed in water. The dye bath thus prepared is heated to a temperature approximating 45 55 C. and the textile material to be dyed is immersed in the dyebath, following which the temperature is gradually raised to 8090 C. and maintained at this temperature until dyeing is complete, usually one-half to two hours. From time to time throughout the dyeing operation, the material is worked to promote even dyeing.

Upon completion of the dyeing operation, the textile material is removed from the dye bath, washed with an aqueous soap solution, rinsed well with water and dried. In the case of certain of the acrylonitrile graft polymers described hereinbefore it is necessary to dye at the boil for an extended period of time. Instances may be encountered where the fiber is not satisfactorily colored by the dyeing procedure just described. In these instances special dyeing techniques, such as the use of pressure, for example, developed by the art for the coloration of materials diflicult to color may be employed.

Widely varying amounts of dye can be used in the dyeing operation. The amount of dye used can be, for example, to 3 (by weight) of that of the textile material although lesser or greater amounts of the dye can be employed.

The following example illustrates one satisfactory way in which the fibers of the acrylonitrile graft polymers can be dyed using either the non-metallized or metallized azo compounds of our invention. 16 milligrams of dye are ground with an aqueous solution of sodium lignin sulfonate until well dispersed or alternately the dye can be dissolved in 5 cc. of hot Cellosolve. The dispersion or solution, as the case may be, is then poured into cc. of Water to which a small amount of a surface-active agent such as Igepon T Nekal BX (sodium alkylnaphthalenesulfonate) or Orvus (sodium lauryl sulfate-type) has been added. The dye bath is then brought to the desired temperature and 5 grams of well wet-out fibers of the graft polymer are added thereto. Dyeing i continued until the proper shade is reached. From time to time throughout the dyeing operation, the material is worked to promote even dyeing.

The expression propionic-acetic (1:5) acids refers to a mixture of propionic and acetic acids in which there are five parts by volume of acetic acid to 1 part of volume of propionic acid.

The non-metallized azo compounds dye nylon sub? stantially the same shades as they dye acrylonitrile polymers.

Acrylonitrile graft polymers including those of the type specifically described hereinbefore are described and claimed in Coover U. S. application Serial No. 408,012, filed February 3, 1954. 2-amino-S-trifluoromethylsulfonylbenzothiazole is described and claimed by our U. S. application Serial No. 413,954, filed March 3, 1954, now abandoned. 2-amino-6-trifiuoromethylbenzothiazole is described and claimed by our U. S. application Serial No. 413,955, filed March 3, 1954, now abandoned.

We claim:

1. The azo compounds selected from the group consisting of azo compounds devoid of a sulfonic acid group having the formulas:

wherein Ar represents an ortho-arylene radical of the benzene series, X represents a member selected from the group consisting of the radical of a monocyclic benzene compound, the radical of a naphthalene compound, a phenylamino radical and the radical of a styryl compound, Q represents a member selected from the group consisting of a methyl group, a trifluoromethyl group and the radical of a monocyclic benzene compound, R represents a member selected from the group consisting of the radical of a monocyclic benzene compound and the radical of a naphthalene compound, Q represents a member selected from the group consisting of a methoxy group and an ethoxy group and Y represents a member selected from the group consisting of the radical of a monocyclic benzene compound and a trifluoromethyl group and their heavy metal complexes.

2. The non-metallized azo compounds having. the formulas set forth in claim 1.

3. A complex metal compound which contains one of the metals selected from the group consisting of chromium, cobalt, copper, iron, manganese, nickel and vanadium in complex combination with the monoazo compounds having the formulas set forth in claim 1.

4. Complex nickel compounds of the monoazo compounds having the formulas set forth in claim 1.

5. The azo compounds devoid of a sulfonic acid group having the formula:

N wherein Ar represents an ortho-arylene radical of the benzene series and X represents the radical of a monocyclic benzene compound.

6. Complex nickel compounds of the monoazo compounds having the formula set forth in claim 5.

l6 7. The azo compounds devoid of a sulfonic acid group having the formula:

wherein Ar represents an ortho-arylene radical of the benzene series and X represents a phenylamino radical. l0

8. Complex nickel compounds of the monoazo compounds having the formula set forth in claim 7.

9. The azo compound having the formula:

10. A complex nickelcompound of the azo compound having the formula set forth in claim 9.

11. The azo compound having the formula:

12. A complex nickel compound of the azo compound having the formula set forth in claim 11.

13. The azo compound having the formula:

14. A complex nickel compound of the azo compound having the formula set forth in claim 13.

15. The azo compound having the formula:

CH3 s\ O CHzOz CN=NA3H 16. A complex nickel compound of the azo compound having the formula set forth in claim 15.

17. The azo compound having the formula:

18. A complex nickel compound of the azo compound having the formula set forth in claim 17. 

1. THE AZO COMPOUNDS SELCTED FROM THE GROUP CONSISTING OF AZO COUMPOUNDS DEVIOD OF Z A SULFONIC ACID GROUP HAVING THE DORMULAS: 